One sure way to quickly improve your Portuguese is to get lost... in Brazil. Even if just for a few hours. All of your speaking inhibitions will immediately disappear and you'll be compelled to do the single best thing for improving your skills: speak to a real Brazilian!
Brazilians are a helpful bunch. I've made lifelong friends from asking directions here. Brazilians will generally speaking, go out of their way to be helpful to foreigners. I don't really know why. Brazilians have something extra in their blood.
But do it in Brazil.
Your first experiences asking for help & directions will be confusing. You need to tell them to slow down, and speak clearly. Keep asking the same question until you begin to understand their answer.
You will not understand anything that someone says to you on the street the first few times. And that's why getting lost is the perfect situation for learning. You will be just anxious enough about getting home that you will be forced to speak and understand. It's truly the best way to get over your speaking fears.
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